Fast-growing species shape the evolution of reef corals

Area of Science:

• Marine Biology
• Paleontology
• Evolutionary Biology

Background:

• Ecological interactions are common in high-diversity tropical coral reefs.
• Biotic interactions among reef corals are known on ecological timescales but their macroevolutionary impact is unclear.

Purpose of the Study:

• To investigate the macroevolutionary effects of biotic interactions on reef coral biodiversity.
• To analyze the role of staghorn corals (Acroporidae) in shaping coral fossil diversity trajectories.

Main Methods:

• Analysis of the Scleractinia fossil record.
• Modeling evolutionary rate shifts over the last 3 million years.
• Assessing the impact of Acroporidae diversification on other coral families.

Main Results:

• Coral biodiversity experienced significant evolutionary rate shifts in the last 3 million years.
• Staghorn corals (Acroporidae) had a major impact on other coral groups' diversity.
• Acroporidae diversification during the Pleistocene increased speciation and extinction rates in other families, leading to higher lineage turnover.

Conclusions:

• Biotic interactions, particularly from staghorn corals, have a dual effect on reef evolution, driving both extinction and speciation.
• Staghorn corals may increase extinction via competition and promote speciation as ecosystem engineers.
• Current reductions in staghorn coral cover due to human activity could disrupt macroevolutionary processes vital for modern coral reefs.